This invention relates to viewing apparatus for cassette contained motion picture film strip and more particularly, it concerns an improved cassette well structure for such apparatus and by which a multi-purpose film cassette may be inserted and retained in a proper operational orientation relative to other viewer contained components.
In the recently developed motion picture art, the term "multi-purpose film cassette" has been used to denote a generally parallelepiped housing in which a strip of light sensitive film is initially packaged along with a pod or reservoir of processing fluid such that the film strip may be exposed, processed and viewed by inserting the cassette containing the film strip in a appropriate motion picture camera, and subsequently inserting the exposed film cassette into a viewing apparatus operative to coat the exposed film strip with processing fluid to develop the conventional series of image frames for viewing by projection in a very short period of time. The film strip is connected at opposite ends to a cassette contained supply and take-up spools, the film strip being wound on the latter both during exposure in the camera and during projection in the viewing apparatus by draining the take-up spool and returned to the supply spool on rewinding as well as for processing. Such cassettes are provided with a light reflecting prism by which projection light may be directed from the reflecting surface outwardly of the cassette through the opening provided therein for exposure and projection. Exemplary disclosures of viewing apparatus for handling such cassettes are found in U.S. Pat. Nos. 3,830,564 issued Aug. 20, 1974 to John F. Batter, Jr., U.S. Pat. No. 3,909,120 issued Sept. 30, 1975 to Joseph A. Stella and U.S. Pat. No. 3,941,465 issued Mar. 2, 1976 to Irwin E. Figge, et. al.
While the cassette receiving well of such viewing apparatus represents only a part of the viewer contained equipment needed to process and project the cassette contained film strip, the nature of the general system imposes several requirements on the viewer structure defining the well. For example, the cassette and film strip must be precisely registered with the various viewer contained components operable on the film strip. Because the processing operation involves movement of a liquid processing fluid within the cassette, gravitational orientation is important. Also to accomodate processing, provision must be made for blocking the passage of light to the exposure-projection opening in the film cassette inasmuch as the film remains light sensitive until the processing fluid is actually coated thereon. The sensitivity of the system to require operating condition dictates further that the system be fully automated. Thus, it is desireable that the system operate directly in response to cassette insertion as well as eject the cassette after the completion of a projection and rewind cycle.